Legionellosis results from
infection by a group of bacteria named Legionella.
Many different species
of Legionella are commonly found in the environment, some of which are known to
cause illness in people. In Tasmania, legionellosis is mainly caused by
Legionella pneumophila and
Legionella longbeachae.
Symptoms of legionellosis
include fever, cough, breathlessness, chest pain and diarrhoea. Legionella
generally infects the lung (pneumonia) which often results in severe
illness.
Legionellosis is a disease of
the middle-aged and elderly. Men are affected more frequently than
women.
Legionellosis is usually diagnosed by a series of blood tests.
Occasionally, the organism can be grown from a sample of sputum or lung
fluid.
Legionella longbeachae can be found in potting mixes, compost
heaps and composted animal manures. Unlike other Legionellae it is not found in
water. How Legionella longbeachae are spread is uncertain. The bacteria may be
breathed in or spread from hand to mouth. Spread from person-to-person does not
occur. Legionella longbeachae can remain on hands contaminated by handling
potting mix for periods of up to 1 hour.
The bacteria can be readily
removed from the hands by washing.
Incubation period
2-10 days, usually 5-6
days.
Infectious
period
Person-to-person spread does
not occur.
Control of spread
Exclusion from work is not
necessary.
To minimise the risk of
infection when handling potting mix, gardeners should take the following
precautions:
- wear a face mask
- open bag with care to avoid
inhalation of airborne potting mix
- moisten the contents to avoid
creating dust
- always wear gloves to avoid
transferring the potting mix from hand to mouth
- always wash hands after
handling potting mix even if gloves had been
worn.
These same measures should be
adopted when handling other garden material such as
compost.
Treatment
Antibiotic treatment may be
prescribed by the treating medical practitioner. Some cases may require
admission to hospital.
Legionella longbeachae
infection is a notifiable disease.
Adapted from
"You’ve got What?", with the permission of the Department of Human Services,
South
Australia.